1. Field of the Invention
The present invention relates to a thermal printer and a cutter. More particularly, the present invention relates to a thermal printer and a cutter that can cut a paper in such a way that a printed portion of the paper can be partially cut to leave a plurality connection points.
2. Description of the Related Art
A thermal printer device having a function to automatically cut a roll paper is often incorporated in a POS (Point Of Sale) terminal and a ticket vending machine.
For example, as disclosed in Japanese Laid-Open Patent Application No. 2000-094767, a conventional automatically paper cutting type of thermal printer has a structure such that a cutter device, which is configured as an individual unit, is mounted to a thermal printer body including a thermal head, a platen and a motor. Such a cutter device includes a fixed blade, a movable blade and a motor to move the movable blade.
Accordingly, it is difficult to realize a small-sized thermal printer because the thermal printer includes both the thermal printer body and the cutter device. This difficulty also incurs difficult miniaturization of a POS terminal and a ticket vending machine.
Also, it is desirable that a mobile terminal device has a function to automatically cut a paper. However, such a mobile terminal device cannot include a thermal printer device capable of automatically a paper from the viewpoint of the size, and currently a paper is manually cut in a mobile terminal device.
In addition, a movable blade includes an almost V-shaped blade part configured from a pair of slope edges. When the movable blade moves in a direction to overlap a fixed blade, two contact points between the blade part of the movable blade and a blade part of the fixed move from both sides to the center thereof. A paper is cut by shear force at the contact points.
The movable blade is configured to have one or more notch parts along each of the slope edge of the blade part. The movable blade is controlled in such a way that the movable blade is finally shifted to a desired position. If the movable blade is finally shifted over a short distance, a paper can be partially cut to leave a plurality of connection points. Also, if the movable blade is finally shifted over a moderate distance, a paper can be partially cut to leave one connection point. Moreover, if the movable blade is finally shifted over a great distance, a paper can completely cut.
Such a movable blade is shaped to have one or more notch parts along the slope edges thereof, and the blade part is discontinuously formed. When an outer-side blade part cuts a paper to an end thereof, the cut operation is temporarily halted, and subsequently the paper is cut by an inner-side blade part. In this fashion, a cutting left part is formed at a portion where the cut operation is temporarily halted.
Thus, it is necessary to smoothly restart the cut operation using the inner-side blade part.
In addition, a thermal printer generally prints a paper at the print resolution of 203 dpi with respect to a paper feed direction. Moreover, a thermal printer than can a paper at a higher printer resolution with respect to a paper feed direction, for example, at the print resolution of 300 dpi, is commercially available. For example, such a higher resolution printable thermal printer is used to pint a barcode and others.
Conventionally, an automatically paper cutting type of thermal printer has a structure such that a cutter device, which is an individual device, having a fixed blade, a movable blade and a motor to move the movable blade is mounted to the thermal printer body having a thermal head, a platen and a motor. It is difficult to shorten the height of a thermal printer having such a structure. In order to overcome this difficulty, a thermal printer designed to shorten the height thereof by providing a cutter at a portion of the thermal printer is proposed. In this thermal printer, a first module having a thermal head, a fixed blade and first and second motors is detachably coupled with a second module having a platen roller and a movable blade. The platen roller is rotated by the first motor, and the movable blade is sled by the second motor.
In order to manufacture two kinds of thermal printers, that is, a thermal printer having the structure such that the first module is detachably coupled with the second module and printable at the print resolution of 203 dpi with respect to a paper feed direction, and a thermal printer having the structure such that the first module is detachably coupled with the second module and printable, for example, at the print resolution of 300 dpi with respect to a paper feed direction, a manufacturer needs to separately design and prepare as the first module two kinds of modules: a module having a structure such that the first motor and a gear set from the first motor to the platen roller can correspond to the print resolution of 300 dpi with respect to a paper feed direction and a module corresponding to the print resolution of 203 dpi with respect to a paper feed direction. Thus, if two kinds of thermal printers having the same dimension and the same specification except for the print resolution with respect to the paper feed direction are fabricated, the fabrication cost of each of the thermal printers and the fabrication cost of one type of thermal printer are the same. In other words, it can be expected to reduce the fabrication cost of the individual thermal printers in the case where the two kinds of thermal printers having the almost same specifications are fabricated.